org.nd4j.linalg.schedule.MapSchedule Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2015-2018 Skymind, Inc.
*
* This program and the accompanying materials are made available under the
* terms of the Apache License, Version 2.0 which is available at
* https://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
* SPDX-License-Identifier: Apache-2.0
******************************************************************************/
package org.nd4j.linalg.schedule;
import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.NonNull;
import org.nd4j.shade.jackson.annotation.JsonIgnoreProperties;
import org.nd4j.shade.jackson.annotation.JsonProperty;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
/**
* MapSchedule is a schedule based on specific values in a {@code Map}.
* For example, if the map contains the following: (0,1.0), (10,0.5), (20, 0.2) then iteration/epoch 0 to 9 inclusive
* will have value 1.0, 10 to 19 will have 0.5, and 20+ will have value 0.2.
* Note that the map MUST have a key for position 0 - this is the initial value.
*
* @author Alex Black
*/
@Data
@EqualsAndHashCode
@JsonIgnoreProperties({"allKeysSorted"})
public class MapSchedule implements ISchedule {
private ScheduleType scheduleType;
private Map values;
private int[] allKeysSorted;
public MapSchedule(@JsonProperty("scheduleType") @NonNull ScheduleType scheduleType,
@JsonProperty("values") @NonNull Map values) {
if (!values.containsKey(0)) {
throw new IllegalArgumentException("Invalid set of values: must contain initial value (position 0)");
}
this.scheduleType = scheduleType;
this.values = values;
this.allKeysSorted = new int[values.size()];
int pos = 0;
for (Integer i : values.keySet()) {
allKeysSorted[pos++] = i;
}
Arrays.sort(allKeysSorted);
}
@Override
public double valueAt(int iteration, int epoch) {
int i = (scheduleType == ScheduleType.ITERATION ? iteration : epoch);
if (values.containsKey(i)) {
return values.get(i);
} else {
//Key doesn't exist - find nearest key...
if (i >= allKeysSorted[allKeysSorted.length - 1]) {
return values.get(allKeysSorted[allKeysSorted.length - 1]);
} else {
/*
Returned:
index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The
insertion point is defined as the point at which the key would be inserted into the array: the index
of the first element greater than the key
*/
int pt = Arrays.binarySearch(allKeysSorted, i);
int iPt = -(pt + 1);
double d = values.get(allKeysSorted[iPt-1]);
return d;
}
}
}
@Override
public ISchedule clone() {
return new MapSchedule(scheduleType, values);
}
/**
* DynamicCustomOpsBuilder for conveniently constructing map schedules
*/
public static class Builder {
private ScheduleType scheduleType;
private Map values = new HashMap<>();
/**
* @param scheduleType Schedule opType to use
*/
public Builder(ScheduleType scheduleType) {
this.scheduleType = scheduleType;
}
/**
* Add a single point to the map schedule. Indexes start at 0
*
* @param position Position to add (iteration or epoch index, depending on setting)
* @param value Value for that iteraiton/epoch
*/
public Builder add(int position, double value) {
values.put(position, value);
return this;
}
public MapSchedule build() {
return new MapSchedule(scheduleType, values);
}
}
}